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ISTM that the choice of Intel mobo is mistated. Further, IMO using an ASUS high-end mobo as one test platform and any Intel mobo as the other gives the former at least a 3% - 5% performance advantage. I wonder too, were all of the ASUS mobo's oc features turned off?

"The Test
Our hardware configurations are similar to what we've used in previous comparisons. For this test, we focused on CPUs at or around the Athlon 64 X2 3800+'s $354 price point.

Rendering in 3dstudio max benefits from dualcore cpus. It however, also benefits from hyperthreading if this is a mental ray render. I'd like to see results for the pentium-d and amd-x2 when rendering in 3dstudio 7 with mental ray. I think the advantage is significant, especially in video renders as it's mathematically more effective to have more nodes rendering.

very nice article indeed! know i just received three computers from Dell today with Pentium D processors, so i see the new X2 is a bit faster, but excited to try it out in general multi-tasking environments regardless.

One question i haven't seen answered is: How does a dual-core cpu compare against a true SMP dual-cpu system? Example would be a Pentium D 840 (or AMD X2 4200+) vs. 2x Pentium 4 - 2.8 GHz Xeon system? For the price, dual-core seems great. How does it handle running Windows 2000 Server or 2003 Server or running as an Exchange server?

If anyone has any input or has tried this, I'd be interested in knowing.

Oh... also, since AMDs cache coherency implementation and the way the dual cores work is more efficient than Intel's, so applications that have to pass ownership of cached data (L1/L2) back and forth a lot will be faster on AMD X2 machines. Of course, this type of application behavior is usually considered to be the result of poor design, so use well written apps :) Reply

Actually, I'd give a slight (very slight) edge to Intel's approach on SMP systems....though AMD's Hypertransport is certainly far cleaner on paper, it hasn't paid off quite so well in practice. However, HT is considerably more suited for a NUMA-based multi-cpu architecture than for SMP. Unfortunately, there aren't many NUMA OS's out there at the moment... Reply

One question i haven't seen answered is: How does a dual-core cpu compare against a true SMP dual-cpu system?

Depends. Dual CPU systems and dual core systems both have two cores running in them. The main difference is that two single core AMD machines (two Opterons) can have independent memory banks if you buy an appropriate motherboard. The dual core systems 9(both Intel's and AMD's) share the same pipe to memory. This isn't as big of an issue for AMD parts because the Athlon64 (single core) really doesn't make good use of dual channel memory anyway (dual channel over single channel is at best 20% faster in memory intensive apps while most see around 5%) so neither of the cores in the dual core setup get memory starved unless both cores are running full tilt (by benchmarks, I guess this would mean that if single channel were 1, dual channel were 2, the two cores running full tilt would need 2.4 channel memory to never be starved). The Intel parts, however, will suffer more. Dual channel memory on a P4 can be saturated by a single core so dual cores going all out can become starved a bit worse (one core would be 2, two cores would need 4/quad channel memory to never be starved).

So, your performance will depend on what types of applications you will be running. Reply

Well Im missing the reasons for comparing the 640 Intel,and 630 D Intel when both are less than the AMD 3800+,and 3800+x2.

True if you where to take the 'best of'in performance to price between both Intel,and Amd the 640 Pentium 3.2 would be the comparitor .

Performance alone though,true AMD 3800+ surpasses the P4 640 .The 3500+ AMD 64 would have been a closer comparitive if solely on a price basis.

With both the AMD 3500+,or the Intel 640 to be either choice in that price point to have. They compare in performance as well.Especially since the next Pentium pricepoint the 3.4 Ghz 650 is the closer comparitor.

The 3800+ AMD 939 single is still more expensive than the Dual-Core 830 D . With the newest AMD 3800+ still at the 400$ spot.

Comparing the Intel 640 to the 3800+AMD is lopsided.

The Intel 650 is the closer comparator,in terms of cost.Still though the Intel 640 remains the gulf between them when cost is the comparator.

Im missing reason author chose to compare these specific CPUs. Since the Intel is clearly not in same performance class.Although for even reach of benchmarks,would be the best'of''in price points to beat.Should have compared the Intel 650,to the AMD 3800+.

AMD 64 3500,AMD 64 3700 would have been closer comparitors to cost between the two,to match up performance.Seen the benchmarks before between them.AMD winning some,Intel winning some.Howebeit,the Intel has HT.etc.

Once again, I believe Anand has shown un-biased data. I run a Dell hyperthreading rig, just because its convenient. BUT, as others have pointed, the X2's were designed from the ground up to be dual, on chip. To have to leave the core, and use the FSB, just shows that Intel is playing catch up. Benchmarks can, and often do show whatever the person running the benchmark wishes to show. Anand has ALWAYS, IMHO, tried to show, unbiased, accurate DATA. The basic design of the long piped Pentium will almost always favor Intel in benchmarks which, in essence are SIMD, in nature. That is, processing streams of data, with a single instuction. Price points, for ANY given CPU, GPU, HDD etc will always be Market Driven. The complexities, which go into the pricing decisions are well beyond the scope of this forum IMHO. AMD will continue to offer innovative design, over Intels 'brute force', more megahertz must be better, approach. Reply

The argument "with Intel you'd need a new motherboard" is invalid if you haven't built anything yet and start from scratch. That would easily leave options open for anyone to chose either. I agree that if your budget can handle it, you should at least consider the X2.

People still complaining about the price of the X2 should realize that this is no ordinairy gaming CPU and the newest tech never came cheap. Since the Pentium D is like two cores slapped together, it shouldn't cost anymore than it does.

I wonder if Intel's Pentium D had a slick architecture like the X2, it would be as cheap as the current Pentiums D. It's not the core itself perhaps that increases the cost as it is the tech that connects the two like the X2 does. Yes, that's included in the price of an X2 ;-) Reply

Actually, you are wrong. It is the core itself that increases the cost. Larger core equals less cores per wafer and (generally) more defective cores per batch (if the possibility of a defect happening in one square millimeter is one in X..).

The technology connecting the two, R&D costs, are paid back in the A64's cost. I suppose in a sense they're paid back in every A64's cost, but the DIFFERENCE between the A64 and A64X2 has nothing to do with slick technology. Reply

There is also something to keep in mind, why shouldn't a processor with with a die size of 199mm2 Toledo core cost 75% more then the 114mm2 San Diego core? I mean you still want to get as much profit as possible per silicon wafer. It doesn't really help your bottom line if you sell more silicon area for a lower price to me.

Though since Intel is just basically slapping two cores together with arbiter logic, if one core is defective on the silicon wafer, they can salvage a Prescott core from it, AMD can't do this, due to their Dual core implementation, though if the defect is in the cache, they can sell it as a Athlon 64x2, 3800+, 4200+, 4600+.

AMD's pricing structure though currently allows, for more margins on Dual Core processors while for Intel it is the opposite, margins are higher for their Prescott, Prescott-2M. Though they don't have to put up with this situation that much longer as Intel, has economical NetBurst Dual Cores for 65nm process. Though on that process there ar more interesting Dual cores as well. Reply

> "...why shouldn't a processor with with a die size of 199mm2 Toledo core cost 75% more then the 114mm2 San Diego...It doesn't really help your bottom line if you sell more silicon area for a lower price to me."

Because there are fixed unit costs in addition to the raw cost of processing a square mm of silicon. Costs that add to a lot more than the raw cost itself. You have to package the silicon, test it, pack it, ship it..not to mention R&D it, market it, and sell it. Those costs predominate in most cases. Which is why when AMD or Intel don't cut their prices in half the moment they move to the next lithography node.

Given a zero defect rate, a 75% larger die should be should be maybe a third more costly to sell. But that larger die also increases your defects/wafer by 75% (roughly) as well.

Example. Assuming a 70% yield (30% defect rate) on a single core chip, you'd expect around a 48% yield on the dual-core version. So each wafer gives you (0.75)(.48)/(.70) = 51% of the chips per wafer.

It gets much worse with low yields. For instance, a 50% single-core yield translates to a dual-core yield of a pitiful 12.5%! So when defects are high, you have to stick with small die sizes.
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I don't really call a difference of increases of 9% that much, but I guess it's all a matter of perspective. Though in the end of the day, the difference between Intel Smithfield and AMD's Toledo is no more then 4% approx on die size.

There are also other cost advantages Intel enjoys, remember all 90nm production is on 300mm wafer processing, which allows for less waste and simply more die per wafer, and reduced resource use, while AMD won't be there till Q1 2006 when commerical production begins on Fab 36 and the activation of their Charter partner fab.

AMD's also uses SOI technology, which we see has benefits in curbing leakage, but we don't have a good idea on how much this technology adds to the cost of the wafer, from what I have seen, since AMD's han't made proclamations on how inexepnsive it was to implmement, cost is not a strong point of this technology.

> "AMD's also uses SOI technology...we don't have a good idea on how much this technology adds to the cost of the wafer"

A year ago, SOI wafers were triple the cost of bulk wafers. Probably a good bit less now...and the raw wafer cost doesn't include the processing and consumables cost. Finally, Intel's wafers are hardly bulk-grade either.
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Sounds logcial. What I wanted to stretch is: there is still the difference in development costs for the Pentium D and the X2. The D being cheaper to develop than the X2 and then of course the volumes in which Intel can sell its double whopper. Reply

True enough-- but a die twice as large shouldn't be over twice the cost...unless your defect rate is pretty high. With a high defect rate, a double-sized die doesn't mean half the yield..it means 1/3 or less.

Intel's dual-core dies are twice as large as their single cores...AMDs are a bit smaller due to the already-embedded HT glue. If the defect rates were anywhere close, then AMD should be able to sell dual-core chips for a smaller premium than Intel. Since they aren't (which likely means can't), we must assume they're still having a fairly high defect rate.

They could also just be charging a premium for the hot new thing. I suspect some of it has to do with AMD wanting to be known as high-end.. when people see Athlons in budget PCs all the time, Athlon becomes associated with budget.

Defect rate works too, though. I'm just throwing out other possibilities. Either way, I think we can agree that the CPUs don't cost more because of slick interconnect technology. Reply

Hmmm, hasn't AMD said they've planned for dual core all along and already had tech in their single core chips to support it? So, now they decide to charge for the tech? The thing anand fails to mention is that 40% more money for 10-20% performance gain is not a "clear choice". The choice is much less clear in fact, if you consider you can't buy a X2 3800 yet... Reply

40%? The X2 3800+ is supposed to cost $354, but the D 830 is $318 at NewEgg. That looks like a 10% price increase for a 10-20% performance increase AND a cooler processor. Seems like a fairly easy decision to me.

If you are suggesting that the inability to perform basic arithmetic is a reason to get the Pentium D, I concur. ;) Reply

The AT review deals with the D 830, not the D 820. You used the numbers from the review and made your remark in the comments section of said review, and yet you feel it's obvious that you're referring to an unreviewed product even if you don't explicitly state such?

Let's leave that behind us, though. There is a very simple flaw in your comparison: you're comparing SYSTEM performance differences to PROCESSOR price differences. How about comparing the build prices of an X2 3800+ to a comparably equipped (same amount of memory, same non-core components, all of that) D 820 system, then looking at the performance difference?

If you're too lazy to do the math (and in fairness, it's a PITA to add up components just for the sake of an argument) I'll just explain it simply: it's an 8-15% price boost for 10-20% better performance and a considerably cooler-running processor (and thus, if you plan the system properly, a quieter system).

Before you get defensive, I'm not trying to say that your 820 was a poor choice. I'm certain that you made the perfect choice for your situation. However, it is clear that the 3800+ is a good value in its intended niche. Reply

Seems video games are only benifiting from raw clock speed. The 2.4 single core A64 outperforms the X2 3800 every step of the way. I will be getting one when there is an X2 2.4GHz that isn't $1000. Reply

I dont know if it was includedin the AMD single vs Dual core comparsion, but I would have liked to have seen comparison of 3000+ (newcastle 2.0ghz, 512k cache...hmm i guess thats 754, what they got thats similar on 939, is that the 3200 they talked about?) vs the new 3800 x2, I could go look at old benchmarks, however sometimes they arent similar enough systesm (sometimes diffrent video, hd, benchmark settings). Reply

"The victory is clear and without debate, at the $300 - $400 price point, the Athlon 64 X2 3800+ is the dual core processor to get. "
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No offense Anand, but the 3800+ would have bent an $1100 840XE too but I guess you did'nt want to embaress Intel like that.;) Making 3800+ at any price point the 3800+ is the dual core processor to get. Just look in your forums -- people arn't buying the PentiumD's even at thier rock bottom discount prices. I've counted 44 X2's and one 820D and this is at the >$500 price points of 4200 and above!!! I expect 3800+ to literally explode in sales. Reply

> "Just look in your forums -- people arn't buying the PentiumD's even at thier rock bottom discount prices"Lol, what world are you living in? Intel is forecasting 2 million Pentium Ds shipped by the end of the year...the lowest independent forecasts are 500,000+ by year-end. Thats a lot more than the A64 X2 is going to sell this year.

> "but the 3800+ would have bent an $1100 840XE too but I guess you did'nt want to embaress Intel like that.;) "

I was surprised that no attempt was made (or posted in the review) to overclock the X2 3800+, given that most people reading it here would want to know what headroom it had.

Fortunately most other good sites did overclock it and post their results, and the general consensus is 2.4-2.5GHz was as much as they could do with air-cooling at reasonable voltages. Looks like the X2 3800+ really is all the speed-binned rejects, at least from the samples AMD sent out to review sites. Reply

quote:As for overclocking, we had no problems reaching 2.46GHz with our Athlon 64 3800+ sample using standard air cooling. The overclocking wasn't as impressive as what we saw with the Toledo based Athlon 64 4200+, but we will save a final conclusion on overclocking until we get more Manchester based processors in house.

Well, Anand did to a tiny bit of overclocking, he just didn't do any benches with the overclock. The above snip was taken from the final page of the article.

Apologies to Anand, I was skimming through the article rather than reading it in full, and missed that. Seems like 2.4-2.5GHz is all the current batch of X2 3800+ can do, which is less than impressive. Ordered a X2 4400+ today as a result. Reply

"Except that by the time you get a new motherboard that supports that cheaper Intel chip and the pricier DDR2 memory, any price advantage Intel had is already gone. And the AMD system still outperforms the Intel one 15% in for the 830D and 20% in the 820D. So choose wisely..."

"From what I can see, Intel 955 chipset motherboards are around $180 - $220, which is a lot more expensive than a decent Socket 939 motherboard. SO overall thge system cost is much cheaper than the Intel 830, and very close to the 820."

You guys obviously haven't checked prices lately. At newegg, you can get a nice ASUS 945 board for $130, which while being more expensive than an EPOX 939 at $85, is much lower than "$180-220". Also, 2GB of DDR is $177.98, and 2GB of DDR2 is $186.00. But I agree, it's worth the extra $50 over the Pentium D 820 platform. Reply

IMO Anand's article was the fairest. He compared the Intel 830 to the AMD 3800. Some sites compared the 820 to the 3800+ and it obviously was not fair to Intel to do that.

Also, if you want an entry level processor and want multitasking, you should go with an HT enabled Intel. At 240 dollars, you should be able to buy a 3.2 GHZ Intel processor with HT enabled, which will perform WAY better at single threaded tasks and perform well in some multithreaded applications. Thats what ENTRY is. You sacrafice future performance for performance right now.

Finally, Anand, I would have liked to see the 3800+ compared to the 3.2 GHZ Intel Dual core processors. Why? Because AMD's PR numbers for single threaded applications indicate that the 3800+(2.0 GHZ with 512 Cache AKA the 3200+) should be comparable with the 3.2 GHZ processor. You shouldn't soely compare the processors on price, but also the PR system :). A 3.0 and 3.2 Intel Dual core comparision with the 3800+ X2 would have been a nice...... Reply

There is no reason at this point to go with an Intel based system for general productivity (business, graphics, compression, a/v editing, 3D modeling, CAD) AND gaming (where AMD had always excelled)

I couldn't agree with Anand more. Where you loose single threaded/task performance (from clockspeed) you more than make up for it in multi threaded/task performance. The overclocking potential is also fairly good, 2.46GHz is nothing to sneeze at when your talking about a 2.0GHz budget chip for 350 bucks.

Also, comparing 512KB dual cores to 1MB dual core's at the same clock speed, there is little performance difference because since the cores communicate directly via L2, not via HT (or bus like Intel) your theoretical performance-based L2 is 1MB and 2MB respectively. AMD's memory controller is so efficient to begin with that the difference between 1MB and 2MB L2 cache is very little.

The cache's are also independent (like they always have been, ie L1 and L2 being non-consecutive) so they don't hold the same information.

Whatever, point of entry into dual core is $250. Like it or not, if someone wants it for what I said, than the cheapest way to get there is with an Intel chipset with built-in graphics and the P4 D820. For my personal computer I'd go with the AMD, but for a cheap PC that will be good for everything but gaming, the Intel solution is the way to go.

Uh, funny, My Intel D820 runs the same games I was running on my AMD 3500 and I can't tell any difference.
And, no the 945 mobos and DDR2 memory aren't any higher in price if you look...
I voted with my $$$. :) Reply

Just because you can't tell the difference doesn't mean that one doesn't exist. This is stock advice. And anyway, this isn't about whether or not you're happy with your purchase decision, it's about whether that purchase decision is a genuinely good choice. Bose speaker buyers are generally happy with their purchases, but that doesn't mean Bose speakers are any good. Reply

Well, I have my systems OC'd, the D820 by 10% and my ADM 64 3500 by 20% and ran x2demo. Both systems running Geforce 6600GT. Came out virtually the same frame rates. As I paid less $$$ for my D820, yes I'm happy with it for what I do... Any other analogies that might help? Reply

I never said it was a bad choice, krisia, only that you can't extrapolate from your own very limited experience and tests and say that it must be a better choice in general. I'm sure that you made the perfect choice for your situation, but that doesn't mean it's the right choice for everyone/anyone/someone else.

Again, the Bose analogy. A Bose buyer might put their favorite CD in their Bose system and decide that it sounds just fine compared to their neighbor's stereo. They made a fine choice for them, but that doesn't mean it's a choice they should recommend to others. Ever.

Actually, I would say that I have a fairly accurate idea of how hot the 820 and 830 run. The 820 is quite possible-- easy, even, to cool (how could it not be), but the fact of the matter is that it is nearly impossible to get a silent air-cooled system with one, and it is quite difficult to get one that's merely quiet instead of "noise-reduced." If you beg to differ, you'd be arguing with an SPL meter, meaning that you have probably been deafened already.

Also, "whatever" is not an adequate response to "Intel dual core motherboards make up most of the cost difference." Try again. Reply

I do not care that it's faster than Intel's dual core cpu. Intel's CPU is $100 cheaper. If I'm building a new PC for web, office and occasional DVD encode, I'm buying the Intel chip. Plain and simple, the $100 sure as hell makes a difference. No enthusiasts will go for the 3800+ unless he is willing to OC the hell out of it. Your regular guy that just wants a good, stable PC with adequate power to do anything and dual core to be able to encode video and happily keep on making his powerpoint presentation, the Intel chip will aloow him to do so and save a hundred bucks in the process.

AMD's cost much more to make because they must have perfection over two cores on a single die vs. intel who slaps two prescotts together. You pay a performance price for Intels way of doing things which is reflected in the lower price.

Too bad you're only looking at CPU price.. when you consider power, mobo, and ram the pentium dually setup costs more money. Reply

AMD's cost much more to make because they must have perfection over two cores on a single die vs. intel who slaps two prescotts together.

What are you smoking? The AMD X2s are a single chip. The Intel parts are also a single chip. Intel does not "slap" two Prescotts together to make the dual core parts. They are two cores on a contiguous piece of silicon just like the AMD parts are. Now, you can talk about Intel's implementation of dual core logic not being as good as AMD's and the like, but please quit with the myth that Intel's dual core chips are actually MCMs because they aren't. Reply

From what I can see, Intel 955 chipset motherboards are around $180 - $220, which is a lot more expensive than a decent Socket 939 motherboard. SO overall thge system cost is much cheaper than the Intel 830, and very close to the 820. Reply

By that same logic, should Intel cut prices on the Pentium D 830, 840, and EE down to the same price as the Pentium D 820? Of course not, because with higher performance comes higher prices.

Sure, AMD could release a 1.8GHz X2 3400+ at a $250 price point to cross with the Pentium D 820, but before that happens they'll continue to make a profit with what they've got before introducing a new chip which has been artificially gimped in order to meet the needs of the low end/entry market. Reply

Except that by the time you get a new motherboard that supports that cheaper Intel chip and the pricier DDR2 memory, any price advantage Intel had is already gone. And the AMD system still outperforms the Intel one 15% in for the 830D and 20% in the 820D. So choose wisely... Reply

You know what's funny? Most of the customers I've had were more than happy to pay extra to have a PC that ran very quiet and cool. All of them said they'd like that, actually, but most of them added that they wouldn't mind a hefty premium. So do you think these customers would bite if I told them that $100 would buy them a faster, more capable, and cooler-running processor?

Oh, it's expensive, to be sure. But saying that no one will ever want it just because you don't is, well, stupid. Reply

"one major flaw in AMD's execution: price"
"AMD's Athlon 64 X2 was the better overall performer, just at the very wrong price point."

Anand, I wish you and the rest would seriously sit down and think about all the sniping and whining you've done lately about the prices of high(er)-end products. How, exactly, was AMD's price execution flawed? They can only make so many of the X2 chips, and they have been flying off the shelves at and above their suggested price. It's not like AMD's "flaw" was pricing them so high no one was buying them and they were gathering cobwebs in warehouses. What's "wrong" about this price point?

Let's look at it this way, is AnandTech "flawed" and "wrong" in its advertising pricing? I mean you could sell front-page add space for $5 per month. Or do you charge a reasonable price that keeps ads to a reasonable (non-overwhelming) number of ads on a page, without pricing so high that there's huge droughts of no ad revenue?

I couldn't care less if you were to deem products "too high to recommend to most users for their budgets and needs" and the such. But it's pretty petty that you and the crew constantly take slaps at products and their manufacturers because they're priced higher than we'd WISH they'd be, but still selling quite well and making those who can afford them quite happy. A new Corvette costs more than a Neon. This isn't "flawed" or "wrong." It's just another factor to take into consideration when purchasing and recommending. Now if something is seriously overpriced for its ability, by all means point it out. But stop coming across like you have no clue that the prices for higher-end parts ramp up quite steeply, and deservedly and understandably so. Been this way for decades and will continue to be this way for decades to come. Reply

From AMD's perspective, there may be nothing "wrong" with pricing X2 chips far higher than two equivalent single CPUS...but from the consumer's persective, such a price point is most certainly flawed.

So are you a consumer or an AMD stockholder? It should be obvious that-- for the average consumer-- a second core priced far above the first is a poor purchasing decision, and that such pricing will never lead to significant market penetration. Reply

But that's just it, AnandTech is taking the stance that it is wrong from AMD's perspective, not from the consumer's. That is where I think they've gone off track. As far as a second core being priced far above the first, color me unfazed. If somehow AMD or Intel were able to bump single-core clock speed by 50%, would any of us be suprised that the new chip would cost (gasp!) AT LEAST double the price? On a dollars-per-Mhz scale, of course it's a loser. On a "getting my hands on a high-end performer" scale, it's easily a winner at double the price. Look at how much more we pay for just a 20% bump in single-core clock speed, and yet it doesn't generate the kind of whining that adding a whole second core and cache does.

"...Such pricing will never lead to significant market penetration".
Funny, last I heard X2s were selling very well, especially when measured against AMD's ability to produce them. As always, when production ramps up the cost will go down.

The other thing I'd add is that it's my understanding that the 820, a very good performer for its price, is that it's a subsidized chip. I gather (though could be wrong) that Intel sells them for zero profit, or even loses money on them to bump up market share. If that's the case, then its pricing is somewhat an exception and that should be provided as appropriate context in any comparison as Intel has the size and cash to do this, where AMD doesn't. Reply

> "But that's just it, AnandTech is taking the stance that it is wrong from AMD's perspective..."

I think you're reading your own bias into his statements.

> "Funny, last I heard X2s were selling very well, especially when measured against AMD's ability to produce them..."

Actually, they are selling well ONLY when measured against AMD's ability to produce them. An ability which is nearly-nonexistent. A few thousand cpus a month may sound like a lot to you, but it doesn't even pay for lunches at the corporate HQ, much less fund a few new multibillion dollar fabs.

AMD's trickle of high-priced X@ sales was useful for bootstrapping future sales...but for gaining any significant market share-- or even paying off a portion of the X2 R&D costs-- it was a nonentity. As I said before. Reply

But the comparison isn't between an Athlon and a dual-socket Opteron setup...but between AMD and Intel dual-cores. The "flaw" is charging $300-400 for a second core, when Intel will give you one for $100.

Let's face it...while AMD trounces Intel in gaming and other single-threaded apps, performance is neck-to-neck for highly scalable apps...just the ones you'd want a dual-core processor in the first place. AMD can't afford to charge far more than Intel for these cores...not if they want to sell more than a few thousand cpus to the fanboi brigade. They have to bring their prices more in line. A step they've taken with the launch of the X2 3800.

No, in that Toledo die can have 1/2-cache disabled, and run as 512K L2 x 2

However this page is silly for other reasons-- they probably had a Manchester 4200+, not Toledo, and more importantly, it just shouldn't make any difference, as the 89W TDP is given to both Toledo and Manchester 4200+s. They are both Rev E parts, and with equal frequency and enabled cache size, should on average be almost identical, as not much changed from E4 to E6.
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(2) Toledo vs. Manchester doesn't really matter in terms of power. Rev E4 and E6 are basically the same. AMD is simply able to choose a lower official TDP for the lower-rated parts (4200+ and 3800+), whether they are made from the Manchester die OR the Toledo die. (Both 4200+ "BV" and 4200+ "CD" receive an 89W TDP from AMD, along with the new 3800+ "BV")
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Higher numbers do not equal higher performance in all of these tests. To quote the review (what, didn't you see the caption?): "The iTunes scores are Encoding Times in Minutes, lower numbers are better."

And no, Intel's dual-cores were definitely available before AMD's. I distinctly remember hearing a lot of complaints about this. The gap doesn't seem that big in retrospect, but trust me, it was there. Reply

Agreed -- sometimes higher is better (frames) and sometimes lower is better (time). So in that regard, wouldn't all the encode tests (and 3dsmax) be measured in time? If so, then AMD would have lost 3 of the 4, rather than the other way around. Gah!

What am I missing here .. are the Windows Media Encoder HD and the Divx 6 Encode measured in some other way besides time? Reply

the intel memory was rated at 3-3-3@533, thats pretty good, i think the lowest you can go on ddr2 is 3-2-2@533, but that would be a lot more than 2-2-2@200 ddr ram, isn't the intel board still 50 bucks more than the amd 939 boards, then the x2 3800 would be a compeititor with the 2.8 p-d but only for a month or two until they get the prices down on the new intel chipsets

though ddr2 seems to have an easier time with larger ram modules, 1gb modules in particular

"Strongest paper launches ever" ??? Face it, you guys blew it in your original X2 article, claiming there would be no retail availability until late this year. Turned out that in June anyone who wanted one could buy one from Newegg or Monarch.

BTW, the 4200+ and 4600+ were Manchester (OPN core code: "BV", Rev E4) cores (147mm^2) when launched. Now there are also Toledo (OPN core code: "CD", Rev E6) versions, but they did not show up until recently.

Check the Desktop Processor Quick Reference Guide (and OPNs of parts sold since June from various vendors-- the 4200 and 4600 were "BV" Manchester parts):

Why no details on the testbed for each platform, specifically memory speeds used? It makes me wonder if the comparison used pricey low-latency ram for the X2 and bargain-barrel chips for the Pentium D..

Also the article states "While AMD scales slightly worse than Intelin the MMCC Winstone and Multitasking 1 tests, AMD scales a lot better in the last two tests...". In one of those tests, AMD's "slightly worse" is 5.7%...whereas AMDS "a lot better" result on one of the other two was a measly 2.9%.

A 5.7% drop is "slightly worse", but a 2.9% increase is "a lot better"? What's funny is this obvious distortion was likely done subconsciously by the author, in his desire to boost his favorite.

When are you fanboys going to learn that processors are TOOLS. Use the best one for the job at the time...don't fall in love with them. If you were plumbers, you'd probably be masterbating each night with your pipe wrenches. Reply

I found (at least) some of the conclusions about “AMD's Efficiency Advantage?” bogus.
The biggest error (and most obvious) is in the Winstone multitasking test 1, where the author commented that AMD is “significantly worse in the Multitasking 1 test”.
In that test duel core had no benefit because a single core AMD processor can handle that test without the need for a duel core. Looking at the actual numbers for that test on the “Multitasking Performance” page not only shows that the faster clocked single core AMD scale almost perfectly (based on clock speed) against its slower clocked duel core counterpart but it has the top performance in that test. Without looking at both the actual score and the percent of increase what is being proven has nothing to do with the “efficiency” of a duel core, but more to the point it shows how “inefficient” a single core is in that test. The 0% increase by moving from single core AMD to duel core AMD only goes to show how “efficient” the single core AMD is in that test scenario.
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Aside from being near-intellible, this reply is far off the mark. No matter how efficient a single processor is, one expects two processors to be somewhat faster tha one. If this wasn't true, what would be the point of "duel-core" [sic] processors in the first place?

There is no magic "100% efficiency" level for single a processor that cannot be exceeded. Even if there were, that efficiency would translate to the second core, making it faster as well. Two should be faster than one.

The efficiency being measured is not of the core itself, but of the scalability of multiple cores vs. a single one. In this particular case, there is a "100% efficient" standard-- linear scaling. If two cores run a benchmark twice as fast as one, then the dual-core implementation is 100% efficient...regardless of how efficient or ineffecient the actual cores themselves are.

Read the above carefully and consider it. It's not difficult to understand. Reply

You can expect two processors to be faster than one, but that isn’t always true.

What you failed to understand is the single core AMD processor is not limited by processing power in the Winstone multitasking test 1, so by adding the second core there is basically nothing for the second core to do, hence no performance increase.

Because of this it is inappropriate for the auther to gauge scalability for this test in a negative context as he did when he said “significantly worse”. In fact the worse a single core processor performs the more likely it will see a higher scaling when a second core is added because there is more work for the second core to process.
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> "You can expect two processors to be faster than one, but that isn’t always true..."

Of course it isn't. That's the purpose of this test...to determine the performance increase, if any.

> "...The single core AMD processor is not limited by processing power in the Winstone multitasking test 1, so by adding
> the second core there is basically nothing for the second core to do, hence no performance increase."

Oops, wrong again. You should have realized this simply from the fact that a higher clocked single-core A64 runs the benchmark faster. Claiming this test isn't even slightly CPU-bound and thus the poor result "isn't AMD's fault" is nonsense.

> "...the worse a single core processor performs the more likely it will see a higher scaling when a second core is added..."

Only for tests that are disk or memory-bound. And given the current differences in memory subsystems between AMD and Intel and the highly-integrated nature of AMD's memory controller, the "efficiency" of AMD's dual-core implementation is pretty much indistinguishable from the efficiency of their memory system.

So that just leaves highly disk-bound tests...which these tests were not. Even if they were, the results would still be valid. After all, if a single-core A64 runs as fast as possible due to disk constraints, then why should anyone spend more money on a dual-core chip?

Of course, one core of an X2 3800 is not nearly so fast as to run any of these benchmarks "as fast as theoretically possible". If multiple cores don't score higher, then its indicative of an underlying scaling issue, either with the chip or the test itself. Any other conclusion is nothing more than apologism and wishful thinking. Reply

Processing POWER is not necessarily the same as processing SPEED.
Using an analogy may be the only way to explain this to you.

If you are given a task that is simple for you to accomplish, maybe something like moving two bricks 50 feet, having a second person help you will not result in you getting that task done any faster. The only thing that will make this task faster is if you run instead of walk. That difference is speed not power.

On the other hand if the task is more demanding, this time you need to move a 100 bricks 50 feet, then the second person should be able to cut that time in half if both of you move the same amount of bricks at the same speed.

I hope that wasn’t too hard for you to understand.

To go one step further, If in the first scenario (when you had to move just two bricks) if you only move one brick at a time then adding a second person (also capable of moving one brick) will show 100% scaling.

This demonstrates what I said about a poor performing processor will see a higher scaling when adding a second core, proving my point that higher scaling “shows how “inefficient” a single core is in that test”, not how efficient a duel core is.

To even attempt to show scaling efficiency in the manor that was done in the article is questionable, and to use a test that was not only less than processor limited on duel core, but less than processor limited on a single core was ignorant (again I am talking processor limited in terms or computational power not speed).

Since adding a second core does not change memory bandwidth or disk access time I don’t know why you even brought this up, as its irrelevant.
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> "This demonstrates what I said about a poor performing processor will see a higher scaling when adding a second core..."

Are you stupid? Your analogy-- muddled and poorly phrased as it is-- proves my point. Not yours. We're discussing a multitasking benchmark. Got any idea what the "multi" in multitasking means? More than one. A single core executes ONE thread at a time. This benchmark has multiple threads running at once.

To translate this back to your analogy, a single core cannot carry two "bricks" (threads) at the same time. It carries one-- partway or all the way-- then has to "run back" to carry the other one. And so on until the job is done. Sorry for the kindergarten-level analysis, but your posting history demands it.

Two cores carry two bricks at once...and get the job done faster. If you only had a single brick (a single nonthreaded app) then a second core wouldn't help you. If your second brick only had to move 1 foot rather than 50 (poor app scaling), then a second core would help very little. If your brick-carrying kept being interrupted by a traffic cop (disk or memory bottlenecks) then one core might run as fast as two. But in general-- two cores run multiple threads faster than one.

Get it now? I rather doubt it...but hope springs eternal to the human breast.

> "if you only move one brick at a time then adding a second person (also capable of moving one brick) will show 100% scaling."

Read my explanation above...then take your foot out of your mouth. This statement is the very reason for multicore processors. One core moves one brick at a time. Period.

> "Since adding a second core does not change memory bandwidth or disk access time I don’t know why you even brought this up, as its irrelevant. "

Again, you fail to understand the most basic concepts. An "app" that does nothing but copy a large file from A to B is disk-bound. Add two cores or a hundred, and it won't speed up. That's why this is relevant.

Of course, no app or benchmark is ever 100% disk-bound. But the faster the processor, the more impact a bottleneck will have. An infinitely fast single-core cpu will not run apps in zero time...it'll just spin, waiting for memory or disk. And adding a second core to such a cpu won't yield any gain...BECAUSE of the bottleneck.

Get it now?

Of course, our scenario of "Multitask Benchmark 1" and the A64 3800 isn't even close to this scenario. I only mentioned it to discount it, as it was the only quasi-reasonable explanation you could have believed the drivel in your first post. I see otherwise now...you were simply wholly and utterly clueless from the start.

Since you seem to believe that we should see an improvement in any multitasking test no matter how simple those tasks are explain this.

If we know that adding a second core will increase performance (as indicated by 9.1% increase of the duel core PD over a single non-HT P4 for the test in question) then why does the AMD duel core show no increase in performance?

It can’t be that the AMD duel core is not functioning, because we can tell that it is functioning based on all the other tests.

Since this IS a multitasking benchmark (as you made sure to point out) maybe you would like a stab at this question also.

How is it that a duel core PD at 3.0GHz it is still not able to beat (or even match) a single core AMD at 2.0GHz?
It’s not like this test was designed to cripple an Intel processor (this test runs “files copy in the background while the script runs Microsoft Outlook and Internet Explorer in the foreground”).
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> "If we know that adding a second core will increase performance...why does the AMD duel core show no increase in performance? ...It can’t be that the AMD duel core is not functioning..."

Easy question. Why? Because some resource in contention between the two cores is negating whatever slight gain the second core can offer.

Your notion that a second core that works in ANY case has to work in ALL cases is terribly misinformed. Consider Intel's HT for instance. Two virtual cores...but given they share so many resources between them, there are many cases where HT not only shows no performance gain, but an actual performance drop.

It's less common with two physical cores, or even two physical processors...but it can and DOES happen. Intentionally writing code that runs slower on a duallie (even 100X slower) is easy. Writing it accidentally is very possible as well.

Now here's the part you actually have to use your brain to understand. Take a deep breath and think before reading on. There are implementation differences between AMD and Intel's dual core designs. That means they share different resources, and to differing degrees. Meaning a program that causes some slight contention on Intel may cause more on AMD...or may cause none at all. Whereas different code may contend in totally different areas, and show a totally reverse pattern.

So Anand is calling a 5.7% Intel advantange "slight" but a 2.3% AMD advantage "significant".

Toss out the Intel Dual Core + HT row -- a fairer comparison in my opinion) and Intel does even better. Add in the non-dualcore Intel row and Intel does better on MT1 and worse on MT2...but not even the most strident AMD fanboy could call that a fair comparision. Reply

Not to take sides, but this was just comparision of AMD singc vs AMD dualc % vs Intel singc vs Intel dualc. The performance advantage wasnt direct comparison of AMD's dual core vs Intel's dual core. Disreguard if you understood this, but to simplify the explantion. Say AMD single core has benchmark of 100, Intel single core (/w ht lets say) is 90; then AMD dual core (same cache/mhz) has benchmark of 120 (20% increase) while Intel Dual core was 115 (27.7*% increase). Showing Intel's second core gave 7.7*% more power vs AMD's second core over its first. The purpose of this comparison was to try to find a benchmark (since none seem to be known to the author at this time) to see whose dual core implimentation is more "effiecent". Also possible the author, when describing "significant" or "slight" he did not seem to be averaging their numbers between ht and no ht, but simply sticking with one, at least I would assume this to be the case. Reply

The interesting part of his statement is the fact that the AMD Dual Core actually beats the Intel Dual Core in MMCC Winstone. I agree though that a 9.1% improvement is more than slightly better than 0%. Reply

Good for you... I simply cannot login/post comments while using firefox. It seems to accept the login, as it doesn't spit back an "invalid" message but shows me the login form again, and no links to "post" or "reply". Probably just a cookie issue but I tried turning my security down a little and it still didn't work... is Anandtech requiring a 3rd party cookie to be set just to post comments... ? Reply

For a short while a month or so back, I was "approving" each cookie individually, and anandtech insisted on planting a cookie until I said "block site completely" - forgot about that until today. Finally able to post in Firefox now! Reply